With the popularity of mobile terminals, such as smart phones, and the improvement of metal housing manufacturing process, a metal housing is employed in more and more mobile phones and makes the smart phone more advanced due to its high heat dissipation capacity, high mechanic strength (enabling the metal housing to be thinned so as to meet the need of consumers for ultra-thin equipment), unique metallic luster and fashion appearance. As the metal housing may produce electrostatic shielding effect which affects the emission and reception of radio frequency, the metal housing is generally designed in a three-section manner, in which a body and two end pieces of the metal housing are spaced apart by providing a groove therebetween, and connected to form an integral housing by a plastic injected into the groove and molded therein. In this way, the end piece of the metal housing is connected to the PCB board via a spring piece, such that the end piece possesses a signal radiation function and becomes a part of the antenna.
However, in order to improve the integrity of the metal housing, a width of the end piece of the metal housing narrows down. In such a case, the overall structure of the antenna will become more complex when the spring piece is in direct contact with the end piece, affecting assembly efficiency.